A conventional virtual machine monitor (VMM) runs on a computer, hereafter called the “host platform”, and presents to other software the abstraction of one or more virtual machines (VMs). Each VM functions as a self-contained computer, running its own “guest operating system” (guest OS), which can be a standard OS for the computer being virtualized (e.g., Microsoft® Windows® for a Personal Computer). Currently, each guest OS is responsible for solving power management problems. However, some OSes are unable to manage the power consumed by the host platform because they are not equipped to handle power-management signals sent by host platform hardware. In addition, the guest OS expects to run on a dedicated computer rather than in a VM and is unaware of other VMs that may be running on the same host platform. As a result the guest OS may, in its attempts to provide power management of the VM that it is running in, conflict with the power management actions or expectations of other guest OSes running in other VMs. Accordingly, guest OSes running in multiple VMs cannot be allowed to directly provide power management of host platform hardware resources.
Therefore, there is a need for an alternative power management mechanism that will provide more efficient use of computing resources in a virtual machine environment.